There are many types of bioplastics globally, but no other bioplastic stands out more than PLA, which is constantly used for 3D printing around the world. Find out more about this thermoplastic made of corn.
Is Polylactic Acid a Bioplastic?
Is PLA a bioplastic?
Polylactic acid or PLA is a type of bioplastic or biobased plastic developed to lessen the impact of polymers or plastics on the environment. PLD degrades over time and can also be recycled, which is a plus since some plastics are difficult to recycle, and thus, they become additional burdens to bear by the environment.
What is truly fascinating about PLA is that it is the product of refining glucose, or in some cases, glucose, until a highly pure organic polymer emerges from the process. PLA has been around for decades and is used extensively in textile industries, packaging different kinds of products, and more recently, it has also been adopted for engineering uses.
The production of PLA is strongly linked to biotechnology, and there are many types of blends of PLA, too. The most inert is highly pure PLA, which does not have any inclusions at all.
Pure PLA is also called electrospun PLA. Then there are the nano blend PLAs and the composite PLAS combined with materials like nanotubes and metal oxides. These additional materials are added to PLA to manipulate the polymer’s physical characteristics – usually to make the polymer more durable, pliant, etc.
The more advanced manufacturing processes for PLA allow for larger pores to contain pharmaceuticals for direct application to patients. These highly porous PLA materials are also highly biodegradable and are even friendlier to the environment. The introduction of nanotube technology has greatly expanded the use of PLA in different industries.
Is PLA biodegradable?
We can confidently state that PLA is indeed a biodegradable polymer. Apart from being a marketing term, PLA stands out among other plastics used extensively in different industries because it can biodegrade over time – in a matter of months, even if the conditions are right. However, we have to admit that sometimes, biodegradable is a stretch too far and too thinly, as in biodegradable plastics. For one, PLA is certainly not like kitchen refuse, where it only takes a matter of days before nature can claim the material again, doing no damage at all to the environment. Kitchen waste does not have any long-standing ill effects on the environment, and it can even be used for composting and making gardens bloom.
On the other hand, Plastics will only degrade after several hundred years, making them one of the biggest threats to nature and humans at the moment. Plastics are a huge threat to the environment because they pollute everything, from the land to the water. Plastic waste in the ocean is another issue altogether as it harms the marine ecology in so many ways.
Is PLA Plastic Toxic?
PLA is tagged as nontoxic, and on its own, it is unlikely to cause any more injury to a human or animal. However, just because PLA is derived from cornstarch doesn’t mean it is completely safe to eat. For one, PLA is rarely manufactured in its pure form. As we have mentioned earlier, PLA can be combined with other materials like metal oxides to toughen up the material. The presence of other chemical compounds makes the end product unsafe for consumption.
People often ask if it’s okay for their pets to ingest PLA materials. As you know, PLA is one of the most popular thermoplastics used for 3D printing. People are now using PLA to print decorations and other pet care items, especially toys and other aesthetic items. Sometimes, animals take a bit from the physical objects in their environment, raising the question of how safe it is for animals, too?
Is PLA Plastic BPA Free?
PLA does not contain BPA, so it is a properly BPA-free thermoplastic. PLA is derived from a renewable source of raw material, from different crops such as starch from Asia and chips. Tapioca starch is also used in producing this awesome organic polymer. But that doesn’t mean that PLA isn’t reliable or durable. PLA has the same characteristics (almost) as conventional polymers and is just as durable. PLA is so reliable that it can be used for both engineering and medical purposes.
PLA plastic properties
Below are some characteristics of PLA:
- The exact characteristics of PLA are dependent on what was added to the PLA in the first place. Regular PLA used for 3D printing are often combined with special dyes for obvious reason. Pure PLA is either white or colorless, in filament form.
- PLA combined with polyester is very durable and can be used for all kinds of textile applications. This is called the polyester PLA blend. The variability of the percentage of PLA will determine the specific strength of the final product.
- The settings of the injection molding process also have an impact on the physical characteristics of PLA. Unblended PLA is tough, but the addition of a second material often toughens the composition properly to enhance mechanical strength.
How to Make PLA Plastic?
How is PLA made?
The most basic description of PLA’s production process is it is essentially fermenting a source of carbohydrates under very controlled conditions. The fermentation process’s goal is to eventually produce lactic acid, or what is called lactide monomers. The product of carbohydrate fermentation will eventually be turned into a polymerized form, called PLA. Corn is first milled (wet milling) until the cornstarch is naturally separated from the husk and all the other unnecessary elements. The separated starch from the corn is then combined with enzymes and acid before introducing the heat source. The heating of the separated starch produces a chemical breakdown, which then produces D-glucose, also known as corn sugar. The resulting corn sugar eventually breaks down further into L-lactic acid. The L-lactic acid is essentially the foundation of the PLA that we are all familiar with right now. There are two methods of creating PLA. The first method focuses on using lactide, while the second one is direct polymerization. Either way, the desired PLA emerges from the reactions.